W14×370 Steel Beam
A W14×370 is a wide flange steel beam 17.9 inches deep with 16.5-inch flanges, weighing 370 pounds per foot. In ASTM A992 steel (Fy = 50 ksi) it has a design bending strength of 2,760 kip-ft (LRFD) when its compression flange is braced, and a design shear strength of 891 kips.
Design a W14×370 beam Opens a 27 ft span in the free beam designer.
W14×370 dimensions
| Dimension | Value |
|---|---|
| Depth, d | 17.9 in |
| Flange width, bf | 16.5 in |
| Flange thickness, tf | 2.66 in |
| Web thickness, tw | 1.66 in |
| Distance to web toe of fillet, kdes | 3.26 in |
| Distance between flange centroids, ho | 15.24 in |
| Cross-sectional area, A | 109 in2 |
| Weight | 370 lb/ft |
Dimensions are AISC design values. Detailing dimensions are rounded to the nearest 1/16 in.
W14×370 section properties
| Property | Strong axis (x) | Weak axis (y) |
|---|---|---|
| Moment of inertia, I | 5440 in4 | 1990 in4 |
| Elastic section modulus, S | 607 in3 | 241 in3 |
| Plastic section modulus, Z | 736 in3 | 370 in3 |
| Radius of gyration, r | 7.07 in | 4.27 in |
| Torsion and slenderness | Value |
|---|---|
| Torsional constant, J | 222 in4 |
| Warping constant, Cw | 116000 in6 |
| Effective radius of gyration, rts | 5.00 in |
| Flange slenderness, bf/2tf | 3.10 |
| Web slenderness, h/tw | 6.89 |
W14×370 bending and shear strength
For ASTM A992 steel (Fy = 50 ksi, E = 29,000 ksi) per AISC 360-16. Its flanges and web are compact for bending, so with its compression flange braced it reaches its full plastic moment.
| Strength | LRFD | ASD |
|---|---|---|
| Bending, compression flange braced | φMn = 2,760 kip-ft | Mn/Ω = 1,836 kip-ft |
| Shear | φVn = 891 kips | Vn/Ω = 594 kips |
If the compression flange isn't braced, the beam can buckle sideways before it yields. Up to Lp = 15.1 ft between braces it keeps its full strength; past Lr = 147.9 ft it buckles elastically. With uniform moment between braces (Cb = 1.0):
| Unbraced length, Lb | φMn (LRFD) | Mn/Ω (ASD) |
|---|---|---|
| Braced | 2,760 kip-ft | 1,836 kip-ft |
| 10 ft | 2,760 kip-ft | 1,836 kip-ft |
| 15.1 ft (Lp) | 2,760 kip-ft | 1,836 kip-ft |
| 20 ft | 2,717 kip-ft | 1,808 kip-ft |
| 30 ft | 2,629 kip-ft | 1,749 kip-ft |
| 40 ft | 2,541 kip-ft | 1,691 kip-ft |
| 50 ft | 2,453 kip-ft | 1,632 kip-ft |
| 60 ft | 2,365 kip-ft | 1,574 kip-ft |
| 70 ft | 2,278 kip-ft | 1,515 kip-ft |
| 80 ft | 2,190 kip-ft | 1,457 kip-ft |
| 90 ft | 2,102 kip-ft | 1,398 kip-ft |
| 100 ft | 2,014 kip-ft | 1,340 kip-ft |
| 110 ft | 1,926 kip-ft | 1,282 kip-ft |
| 147.9 ft (Lr) | 1,593 kip-ft | 1,060 kip-ft |
A beam with a uniform load between braces has Cb above 1.0 (1.14 for a simple span braced only at its ends), so these values are conservative. The beam designer works out Cb for every segment between braces.
W14×370 load table by span
The largest uniform load a simply supported W14×370 can carry, in kips per foot, with its compression flange braced along its length (by a floor or roof deck, for example). The loads include the beam's own weight of 0.370 kips per foot.
| Span | Factored load (LRFD) | Allowable load (ASD) | Load at span/360 | Load at span/240 |
|---|---|---|---|---|
| 9 ft | 198.1* | 132.1* | 320.6 | 480.9 |
| 11 ft | 162.1* | 108.1* | 175.6 | 263.4 |
| 13 ft | 130.7 | 86.9 | 106.4 | 159.6 |
| 15 ft | 98.1 | 65.3 | 69.2 | 103.9 |
| 17 ft | 76.4 | 50.8 | 47.6 | 71.4 |
| 19 ft | 61.2 | 40.7 | 34.1 | 51.1 |
| 21 ft | 50.1 | 33.3 | 25.2 | 37.9 |
| 23 ft | 41.7 | 27.8 | 19.2 | 28.8 |
| 25 ft | 35.3 | 23.5 | 15.0 | 22.4 |
| 27 ft | 30.3 | 20.2 | 11.9 | 17.8 |
| 29 ft | 26.3 | 17.5 | 9.58 | 14.4 |
| 31 ft | 23.0 | 15.3 | 7.85 | 11.8 |
| 33 ft | 20.3 | 13.5 | 6.50 | 9.76 |
| 35 ft | 18.0 | 12.0 | 5.45 | 8.18 |
| 37 ft | 16.1 | 10.7 | 4.61 | 6.92 |
| 39 ft | 14.5 | 9.66 | 3.94 | 5.91 |
| 41 ft | 13.1 | 8.74 | 3.39 | 5.09 |
| 43 ft | 11.9 | 7.95 | 2.94 | 4.41 |
| 45 ft | 10.9 | 7.25 | 2.56 | 3.85 |
- Factored and allowable loads are limited by bending, or by shear where marked *.
- The deflection columns are the service loads that make the beam sag span/360 or span/240. Compare span/360 with the live load alone and span/240 with dead plus live load, the usual floor limits in IBC Table 1604.3.
Reading the table
At a 27 ft span, a W14×370 carries a factored load of 30.3 kips per foot (LRFD) or an allowable load of 20.2 kips per foot (ASD). A live load of 11.9 kips per foot would deflect it span/360, which is 0.90 in. The beam works if the factored load is under the first number and the live and total loads are under the deflection numbers. For other spans, supports or loads, open it in the beam designer, or follow the steel beam design guide to check one by hand.
W14×370 questions
What does W14×370 mean?
W means a wide flange shape. 14 is its nominal depth in inches (the actual depth is 17.9 in) and 370 is its weight in pounds per foot.
How much does a W14×370 weigh?
370 pounds per foot, so a 20 ft W14×370 weighs about 7,400 pounds.
How far can a W14×370 span?
It depends on the load. Braced along its length, it carries 198.1 kips per foot of factored load at 9 ft and 10.9 kips per foot at 45 ft; the load table has the spans in between. Floor beams are often 27 to 36 ft for this depth (span-to-depth ratios of about 18 to 24), where deflection usually governs.
Is a W14×370 a compact section?
Yes. Its flanges (bf/2tf = 3.10) and web (h/tw = 6.89) are both compact for bending in 50 ksi steel.